This invention relates to gas-powered guns, and in particular, guns suitable for firing balls such as paintballs dispensed from a magazine.
A variety of guns have been developed in recent years for firing balls using compressed gas. Many of these guns have been developed for the purpose of shooting paintballs which typically include a special, liquid mixture encased in a gelatin layer that will rupture upon impact of the ball with a target. These guns typically are attached to a pressurized gas source generally in the form of a metal cylinder containing a gas such as CO2, nitrogen or air.
In more recent years, guns for firing paintballs have been developed which are electronically operated. Typically, these guns have a pivotable trigger mounted in the gun body and able to operate a small electrical switch such as a microswitch that is part of an electronic operating and control circuit. In addition to the switch, the electronic circuit can include a suitable circuit board that can be mounted in the handle of the gun, for example, and the circuit can further include a standard battery to provide a source of electrical power.
One known electronic paintball gun is that described and illustrated in U.S. Pat. No. 5,878,736 issued Mar. 9, 1999 to Brass Eagle, Inc. In this known gun, paintballs are loaded through a feed port formed in the top of the breech section at the rear of the barrel. Pressurized gas to propel the paintballs is provided by means of a regulator at the rear end of the gun. Lower pressure gas is provided by means of a second regulator and this gas is used to move the gun bolt and one paintball forwardly to the firing position. This gun is controlled electronically by a circuit board mounted in the grip of the gun and powered by batteries. This known gun also employs a double-acting pneumatic cylinder which has a piston rod with a so-called carrier at its rear end. This carrier can be connected to a hammer by means of a sear which is pivotably mounted on the hammer. There is also a coil spring arranged between the carrier and the hammer to bias these two parts away from each other. Also, the carrier is rigidly attached to the bolt by means of a bent link member. This known electronic paintball gun is relatively complex and requires the use of a number of moving parts for its operation. Also, as indicated, it requires the use of two separate regulators in order to provide pressurized gas at two different pressures.
Another electronic paintball gun is described and illustrated in U.S. Pat. No. 6,003,504 issued Dec. 21, 1999 to NPF Limited. This gun also requires the use of first and second gas pressure regulators and the gun is relatively complex in its construction. The gun employs a pneumatic control valve which receives gas under pressure and directs the gas selectively to a pneumatic ram mounted for sliding movement in a cylinder in the gun between a retracted, cocked position and a forward position in which it opens a valve to admit high pressure gas from a gas chamber to the barrel to fire a paintball. An electrical switch operated by the trigger is connected to an electronic control circuit that is battery operated.
Another known paintball gun or marker is a semi-automatic gun sold under the trade-mark FOKUS by Mokal Inc. of Mississauga, Ontario, Canada. This gun employs a venturi bolt that is connected rigidly to a hammer by means of a pin and that therefore moves with the hammer. The hammer is biased towards its forward firing position by means of a coil spring. A pivoting sear member is able to hold the hammer in the cocked position until the trigger is pulled. When the hammer is released by the sear, it is advanced quickly to its forward, firing position where it strikes the stem of a poppet valve, thereby releasing relatively high pressure gas into the barrel to fire a paintball. It is also known to replace the mechanical trigger mechanism of this gun with an electronic switch operated by the trigger and an electronic control circuit that includes a solenoid. In the known electronic firing mechanism, the solenoid is arranged generally horizontally with its movable actuating member moving in a horizontal direction to engage a special sear with a downwardly extending leg. This special sear has an upwardly sloping leg to engage a recess or notch formed in the hammer. This sear is pivotably mounted by a pivot pin where the downward leg and the sloping leg of the sear meet. This sear is biased to its cocking position by a small spring.
Although the aforementioned known construction for operating a gun firing sear by means of a solenoid will function, this known firing mechanism does suffer from some disadvantages. The small spring employed to bias the sear to its cocked position is subject to wear. Also, in this known arrangement, the sear is biased to press against the actuator of the solenoid and therefore the solenoid is subjected to shock when the gun is fired. Furthermore, this known construction requires the solenoid to be adjusted carefully to its correct position in the gun frame and if this adjustment is not properly done, this can result in unreliability in operation of the gun. In addition, the number of shots that can be obtained from a battery charge is limited and it would be desirable to obtain many more shots from a battery charge. Also, this known construction requires a substantial amount of the internal structure of the gun handle to be removed in order to accommodate the gun firing mechanism, including the solenoid and the sear and this results in a handle which is relatively weak and subject to vibration.
Another problem that has arisen from electronically operated paintball guns is that the compressed gases used to propel the paintball from the barrel can undesirably travel upwardly through the ball feed port, the feed tube and the ball hopper, thereby impeding loading of the paintballs through the feed tube. This problem appears to have arisen in part due to the faster cycle time that can be achieved with electronically operated paintball guns. This problem of upwardly flowing exhaust gases impeding loading arises even though it is known to provide a seal on the bolt to prevent exhaust gases from passing along the side of the bolt and escaping in this manner. In the prior art guns, the seal, if any, rather loosely engages in the breech, thus allowing for back-pressure. The known seal cannot simply be made tighter against the bore in the breech as this would increase the drag on the bolt and would result in inconsistent paintball velocities since the hammer may not hit the valve stem hard enough.
It is an object of the present invention to provide an improved gas-powered gun for firing balls, such as paintballs, dispensed from a magazine, this gun being electrically operated and employing a solenoid to operate the sear mechanism wherein the solenoid has a sear engaging member movable from a lowered position corresponding to the cocked position of the hammer to a raised firing position at which the sear mechanism is disengaged from the hammer.
It is a further object of the present invention to provide a gas-powered gun for firing balls, such as paintballs, which employs a barrel with an open-ended, ball receiving chamber formed in a rear end section thereof and a bolt having a sealing member mounted on a front end thereof and engageable with the barrel, this arrangement effectively preventing backward flow of the exhaust gases after the gun is fired.
According to one aspect of the invention, a gas powered gun for firing balls dispensed from a magazine into the gun is provided, this gun being adapted to be connected to a source of pressurized gas. The gun comprises a gun body, including a gun handle, a breech section and a barrel with the breech section being connected to a rear end of the barrel and capable of receiving one ball at a time through a ball feed port from the magazine. The bolt is slidable within the breech section to advance a ball to a firing position and close off the feed port. A hammer is slidable in a chamber formed in the gun body and there are means for biasing the hammer towards a forward firing position. A trigger is movably mounted on the gun body as is a sear mechanism. The gun has an electrical control circuit, including a switch operable by the trigger. This circuit is adapted for connection to a power source. The gun has a sear mechanism including an elongate sear member movably mounted in the gun body. The sear mechanism is adapted to engage and hold the hammer in a rear, cocked position thereof. The sear member is substantially straight from one end thereof to an opposite end thereof. A solenoid is mounted in the gun body, is operated by the control circuit, and is adapted to move the sear mechanism so as to release the hammer when the trigger is pulled. The hammer, when released, slides rapidly to its forward firing position. The solenoid includes a sear engaging member movable from a lowered position corresponding to the cocked position of the hammer to a raised firing position at which the sear member is disengaged from the hammer. A pressurized gas circuit is able to deliver pressurized propellant gas from the source to the barrel of the gun for propelling one ball at a time therefrom and this gas circuit includes a valve. When the hammer is moved to its forward firing position, it strikes the valve to open it, thereby releasing the propellant gas into the barrel.
In a preferred embodiment, the sear member is pivotably mounted and the sear mechanism includes a spring for biasing the sear member into engagement with the hammer so as to hold the hammer in the rear, cocked position.
According to another aspect of the invention, a gas powered gun for firing balls comprises a gun body including a gun handle, a breech section with an elongate breech chamber formed therein, and a barrel connected to a front end of the breech section. A bolt is slidably mounted in the breech chamber and a hammer is slidably mounted in the gun body. The hammer is slidable from a rear, cocked position to a front firing position. A spring device is provided to slide the hammer rapidly to the front firing position when the gun is fired. The gun further includes a trigger movably mounted on the gun body and a sear mechanism including a sear member movably mounted in the gun body and adapted to engage and hold the hammer in its rear cocked position until the gun is fired by pulling the trigger. The sear member is substantially straight from one end thereof to an opposite end thereof. There is an electrical circuit for moving the sear member to a hammer releasing position, this circuit including a solenoid mounted in the gun body and a switch operated by the trigger. When the trigger is pulled, the solenoid causes the sear member to be moved and thereby release the hammer for sliding to the front firing position. The solenoid includes an actuating member which, when the gun is upright with its barrel extending horizontally, is movable from a lowered position to a raised position so that the actuating member moves the sear member to release the hammer. The gun further includes a pressurized gas circuit for delivering pressurized propellant gas from a source of pressurized gas to the barrel for propelling a ball therefrom when the hammer is moved to its front firing position.
In a preferred embodiment, the sear member is mounted in the gun body so as to be pivotable about a transverse axis located centrally along the length of the sear member. Also, the actuating member is positioned to engage a front end section of the sear member when it is moved to its raised position.
According to a further aspect of the invention, a gas powered gun for firing balls is adapted to be connected to a source of pressurized gas and comprises a gun body including a breech section having an elongate bolt chamber and capable of receiving one ball at a time through a ball feed port provided therein. The gun also has a barrel having a rear end section rigidly connected to this breech section and an open-ended, ball-receiving chamber formed in the rear end section. A bolt is slidable within the bolt chamber to advance a ball into the ball-receiving chamber, where the ball is in its firing position, and to close off the feed port. The bolt has a sealing member mounted on the front end thereof and engageable with the barrel. A trigger is movably mounted on the gun body and the gun also has a hammer mechanism including a hammer slidably mounted in the gun body and means for moving the hammer from a cocked position to a firing position when the trigger is pulled. A gas valve system is mounted in the gun body and is connectible to the source of pressurized gas. This valve system is adapted to release pressurized gas in order to fire a ball from the barrel when the hammer moves to the firing position and thereby opens the gas valve system. When the ball is advanced into the ball-receiving chamber of the barrel, at least a major section of the ball is located within this chamber.
Preferably the sealing member is an annular seal that extends about the circumference of the front end of the bolt and the front end of the bolt is slidable into the rear end section of the barrel so that the sealing member can sealingly engage an inner surface of the barrel.